The transformation lasts for 17.5 seconds the tank will flash blue when 4 seconds remain, and once the time limit expires, the two players split and resume driving as they were before. The shooting player has an infinite number of Green Shells and can shoot in any direction, including sideways and backwards. The player who activated the Fusion Kart shoots while the other player drives this concept is very similar to the double kart concept from Mario Kart: Double Dash!!. When one player from their team uses their item button in order to activate the Fusion Kart, the rear player instantly teleports to the front player (eventually gaining up to 4 positions in the process), and the players' karts fuse together to form a single large kart, called the Fusion Kart.
When a player obtains the special power-up via Item Box, an option to turn into the Fusion Kart is available.
